The herbicides belonging to the class of chloroacetanilides or of thiolcarbamates are very useful compounds in the fight against the weeds infesting agrarian cultivations.
Many of these herbicides, however, exert their toxic action also towards certain useful cultivations such as, for example, maize and sorghum, and, by consequence, being not selective, they cannot be used for the weed-killing of such cultivations.
The availability of antidotes, i.e. of compounds which protect the useful cultivations from the action of the herbicides without contemporaneously reducing their herbicide action towards the infesting plants, permits to make use of these herbicides also for defending those useful cultivations which otherside would be damaged.
Among the main herbicides which prove to be phytotoxic for certain useful cultivations there are those belonging to the class of the chloroacetanilides comprising, for example, N-methoxymethyl-2,6-diethyl-chloroacetanilide (common name: Alachlor), N-butoxymethyl-2,6-diethyl-chloroacetanilide (common name: Butachlor), N-methoxyethyl-2-methyl-6-allyl-chloroacetanilide and the ones belonging to the class of the thiolcarbamates comprising, e.g., N,N-diiaopropyl-S-(2,3-dichloroallyl)-thiolcarbamate (common name: Diallate); N,N-diisopropyl-S-(2,3,3-trichloroallyl)-thiolcarbamate (common name: Triallate); N,N-diethyl-S-(4-chlorobenzyl)-thiolcarbamate (common name: Benthiocarb); N,N-dipropyl-S-ethyl-thiolcarbamate (common name: Eptam).
Compounds belonging to different chemical classes are known, which are capable of protecting useful cultivations from the toxic action exerted by the herbicides. For example, dichloroacetamides useful as antidotes have been described in U.S. Pat. No. 4,021,224 (Stauffer) or in U.S. Pat. No. 4,228,101 (Montedison S.p.A.). 2-chloro-thiazoles disubstituted in positions 4,5, which are useful as antidotes in the defence of sorghum cultivations have been described in European patent application No. 27019 (Monsanto Co.).